Field of the Invention
The present invention relates to an antenna with a radiator fixed by fusion and a method of manufacturing the same and more particularly, to an antenna with a radiator fixed by fusion, which is capable of improving antenna performance by minimizing the thickness of a case covering the outer surface of the radiator, while achieving high manufacturing convenience and yield of the antenna enclosed by a case of a terminal through double injection.
Description of the Related Art
With advance of mobile communication networks, mobile communication terminals supporting the networks have been continuously developed and antennas of the mobile communication terminals are primarily very important in stably receive services provided by the communication networks.
In particular, the antennas require portability and aesthetics of mobile communication terminals. In addition, existing rod antennas have been replaced with built-in antennas mounted within the mobile communication terminals and various types of built-in antennas ensuring performance comparable to the rod antennas appear.
The existing built-in antennas generally include a carrier (dielectric material) made of plastics, and a radiator which is made of highly-conductive metal and includes a protective layer for the metal.
The above-mentioned built-in antennas are manufactured as follows.
The first method is to manufacture the built-in antennas using typical assembling systems, such as joining the carrier to the radiator by means of fasteners.
However, such assembling systems have a problem in that the radiator has to be bent depending on an external shape of the carrier in the process of joining the radiator to the carrier and accordingly a space is formed between the built-in antenna and a cover of a mobile communication terminal combined to tops of the carrier and the radiator, which may result in low space efficiency.
For the purpose of overcoming this problem, there has been proposed an in-mold type antenna manufacturing system as disclosed in KR Patent Reg. No. 1103124.
In this in-mold type antenna manufacturing system, a radiator is put in a mold for plastic injection, a primary injected product with integrated carrier and radiator is manufactured, and the primary injected product is inserted in a mold for case to manufacture a secondary injected product. This in-mold type antenna manufacturing system is capable of forming a curved surface of the radiator depending on a curved shape of the carrier, thereby preventing a space from being formed between the radiator and the cover.
However, in the in-mold type antenna manufacturing system where the carrier and the radiator are integrally injected in the required mold, a structure for fixing the radiator within the mold has to be prepared within the mold, which may result in increased complexity of the mold and hence increased molding and manufacturing costs.
In addition, there may occur a problem of deviation and deformation of the radiator in the processing of injecting resin through the mold.
To avoid this problem, a mold is used to prevent the radiator from being deviated by being partially moved. However, it is difficult for this mold to produce uniform products due to deviations between productions which may be produced by errors of mechanical movement, which may result in a poor yield and high manufacturing costs due to relatively high expensive mold.
Therefore, the in-mold antennas have a problem of difficulty in guaranteeing uniform quality since the structure and position of the radiator may be deformed in the process of the primary injection.
In addition, when the resin is injected in the process of the secondary injection for the case formation, since the case is again formed on the radiator molded in the carrier, the radiator is buried further away from the external due to an addition of the carrier thickness and the case thickness, which may result in rapid decrease in antenna performance.
In addition, it is difficult to form a complex radiator due to limitation in size and shape of the radiator depending on a shape of mold and the injection process is troublesome, which may result in a low yield and high manufacturing costs.